It seems that the fix is not enought this test failed at the flush
import nxs
f = nxs.open("/tmp/foo.h5", "w5")
f.makegroup('entry', 'NXentry')
f.opengroup('entry')
f.makegroup('g', 'NXcollection')
f.opengroup('g', 'NXcollection')
f.makedata('d', 'float64', shape=(1,))
f.opendata('d')
f.putdata(1.23)
f.closedata()
f.closegroup()
f.flush()
f.close()
